The relationship between back muscle endurance and physical, lifestyle, and psychological factors in adolescents.

STUDY DESIGN

Cross-sectional investigation.

BACKGROUND

There is some evidence that interventions directed to improving back muscle endurance (BME) in adolescents are effective in reducing low back pain, with anecdotal evidence of improved performance. However, the mechanisms responsible for this improvement remain unclear.

OBJECTIVE

To identify the relationship between physical, lifestyle, and psychological variables and BME in a large adolescent population, while controlling for back pain and gender.

METHODS

One thousand four-hundred thirty-five adolescents (702 females, 733 males; mean +/- SD age, 14.0 +/- 0.2 years) completed a range of physical, lifestyle, and psychological assessments. The group mean +/- SD height and body mass were 164 +/- 8 cm and 57.1 +/- 12.6 kg, respectively. Linear regression was used to investigate the univariate association between each of the physical, lifestyle, and psychological variables and BME. Backwards stepwise multivariate linear regression was used to determine statistically significant independent correlates of BME.

RESULTS

The final multivariate model explained 15.3% of the variance in BME and included at least 1 variable from the physical, lifestyle, and psychological domains. Adolescents who exercised less, watched more television, had a higher body mass index, sat in a more flexed trunk posture (more slumped), and had lower self-efficacy had lower BME.

CONCLUSIONS

All the physical and lifestyle variables linked with poorer BME performance in this investigation are indicative of reduced back muscle activation and/or deconditioning. Psychological predictors may have direct and/or indirect links with BME.